Evaluation of 850°C wet oxide as the gate dielectric in a 0.8-μm CMOS process

The authors describe a detailed comparison of a 850°C wet oxide and a 900°C dry oxide as the MOS gate dielectric in a 0.8-μm CMOS process. The device fabrication involves a GE 0.8-μm CMOS process. Emphasis is given to poly-Si gate linewidth measurements which are crucial to the interpretation of the results. The comparison of thin oxide integrity, device characteristics, hot-electron reliability, and total-dose radiation hardness between the two oxides is discussed. Specifically, it is pointed out why the PMOS punchthrough voltage requirements mandate the use of a 850°C wet oxide for the gate dielectric